The kiln is fired up to a temperature at which the glaze has melted at work. This temperature is between 950 and 1050 degrees. Once the glaze has melted, the work looks shiny and wet, the kiln is opened, the work is removed from the kiln with sturdy tongs and then placed in a ready metal barrel with sawdust, hay or straw. The reduction (oxygen extraction) occurs because the red-hot work sets the hay on fire. By directly closing the barrel with a lid, the sawdust is smothered by lack of oxygen. After about 15 to 20 minutes the work is removed from the sawdust barrel, cooled in a water container and then soot and straw are cleaned off. The cracks in the glaze (craquelé) are caused by the large temperature change and become black due to the lack of oxygen, as are the unglazed parts.